Walter Douglas Gubler

Walter Douglas Gubler was born on January 28, 1946, in St. George, UT. He graduated from Southern Utah State College with a B.S. degree in botany in 1970 and received an M.S. degree in plant pathology from the University of Arkansas in 1974. From 1974 to 1982, he was a post-graduate research plant pathologist with Ray Grogan at the University of California, Davis, and during this period, began his studies toward a Ph.D. degree in plant pathology, which he received in 1982. He worked as a research scientist with the Campbell Soup Company at their research facility in Davis for a year before joining the Department of Plant Pathology at the University of California, Davis, in 1983, as a cooperative extension specialist.

Gubler has one of the most distinguished and robust programs of extension within the University of California system. During his career, he has presented hundreds of talks throughout California, the nation, and the world. He is recognized as an international authority on grape diseases and his expertise continues to be in great demand all over the world. His international stature is one of the sterling qualifications for this award. He has visited 63 countries to lecture or provide advice on disease problems. His oral presentations are complemented by many extension publications that draw on his mission-oriented research program and are directed to his grower clientele. He provides diagnostic support for farm advisers, faculty colleagues, and growers and processes hundreds of plant samples each year, in the absence of any university support designated for this activity. His record of extending information is truly outstanding and represents exceptional accomplishment. In 1998, Gubler received the APS Extension Award in recognition of his accomplishments.

Gubler leads an active, productive, and vitally important research program on diseases of small perennial fruit crops. His research emphasizes pathogen biology and epidemiology, with the overarching goal of improving disease control and reducing pesticide usage. Major thrusts of his research have been Botrytis diseases of grapes and strawberries, powdery mildew of grapevines and strawberries, and the etiology of new diseases of strawberry and grapevines in California. His research, which significantly impacts California agriculture, is nationally and internationally acclaimed. In recent years, a major focus of Gubler’s group has been fungal diseases of grapes, and they were first to show that leaf removal could be used for control of Botrytis bunch rot. His research has included the development of polymerase chain reaction-based procedures for detection and characterization of species of Eutypa, an important fungal pathogen of grapes. Gubler and his group have established important parameters in the epidemiology of powdery mildew in grapevine. They continue to be world leaders in understanding the biology of this pathogen and the efficacy of various control strategies and have made significant contributions to our understanding of powdery mildew, the most important disease of grape in the world. Gubler’s findings helped to identify critical points in the disease cycle and environmental conditions conducive to pathogen development. The Gubler-Thomas risk assessment model is based on this epidemiological information and is designed to obtain the maximum benefit from minimum applications of protective fungicides. This model is used throughout California and is being adapted for other grape-growing regions in the world.

Gubler’s group also has been very productive in work on the epidemiology of vine decline and esca. Much of this work has concerned the detection of sources of inoculum of a complex of fungi responsible for the disease. Their research included the discovery of critical life cycle stages of these fungi in vineyards, induction of fungal fruiting bodies in the laboratory, and the nature of spore release. Gubler and colleagues first reported the pathogenicity of Phaeoacremonium (Togninia) spp. and Phaeomoniella chlamydospora to grape berries and foliage. They further identified varietal differences in susceptibility to these pathogens. Together, these research publications represent a significant advance in our collective knowledge of grapevine decline and esca. Gubler is recognized as one of the foremost world authorities on these diseases.

Gubler has contributed extensively in teaching, service, and outreach throughout his career, including substantive contributions to APS directly or through programs that impact APS and its membership. Although classroom instruction is outside the scope of his position, Gubler readily contributes when asked and he does so with authority, enthusiasm, and skill. He has mentored many graduate students in plant pathology who have gone on to successful careers. His graduate students have won 16 best paper awards for presentations at the APS Pacific Division meetings. Gubler’s service at the campus, state, national, and international level is exemplary. Most recently, he has represented the University of California on committees related to grape and strawberry research and production in California. Internationally, Gubler was a member of the Vinelink International Committee on Grapevine Trunk Diseases and served as chair of the Vinelink International Committee on grapevine powdery mildew from 1998 to 2006. He also serves on the International Workgroup on Powdery Mildew and Downy Mildew of Grapes and chaired that group in 2003-2004 and has been a member of the International Grapevine Trunk Disease Workgroup Steering Committee since 1999.

Gubler’s service to APS is also notable. He has been a member since 1974 and served on committees such as the APS Intellectual Property Rights Committee (1999–2000), Graduate Travel Awards (1999), Extension Committee (1996–1999), and New Fungicides/Nematicides Committee (1996–1998). He has been especially active in the APS Pacific Division, serving as an elected officer since 1998 and most recently served as president of the division in 2007-2008. In 2006, his contributions were acknowledged with the Pacific Division Lifetime Achievement Award, in recognition of his involvement in the division and for his overall productivity in plant pathology. In addition to the aforementioned awards, he has been recognized as an honorary member of PAPA (1992), received the Chevalier de L’Ordre des Coteaux De Champagne (1995; France), and was bestowed the Southern Utah University Eccles Foundation Alumni Award (2003). Gubler’s accomplishments in all areas combine to create a package of extraordinary contributions to plant pathology and to APS.